1. NAME AND TITLE
FORSEN: A Multigroup Processing Code for Use with Sensitivity Profiles to Assess the
Effect of Cross Section Changes.
Brookhaven National Laboratory, Upton, New York.
Southern Company Services, Birmingham, Alabama.
3. CODING LANGUAGE AND COMPUTER
Fortran IV; IBM 360/370.
4. NATURE OF PROBLEM SOLVED
The FORSEN code computes spectrum-averaged group cross sections for two input cross-section
files and provides systematic information for use with sensitivity profiles to estimate the effect due to
changes between the two sets (e.g., ENDF/B-IV vs. ENDF/B-V evaluations).
5. METHOD OF SOLUTION
The input to the code is provided by RESND1-LINEAR2 -SIGMA13 output in ENDF format. Two
input files can be processed simultaneously. The output is the spectrum-averaged cross sections and
their corresponding percent changes between the two input data sets over a specified number of groups
(up to 200). The percent change in group-averaged cross sections between two data sets, e.g.,
ENDF/B-IV and V, for a particular material is used in the SENTINEL4 code to evaluate the sensitivity
of integral parameters of selected fast and thermal benchmarks to the change in certain basic nuclear
data (e.g., ENDF/B-IV and V). In the present version of the code only four reaction cross sections,
namely, the total (MT=1), elastic scattering (MT=2), capture (MT=102), and fission (MT=18), are
6. RESTRICTIONS OR LIMITATIONS
The number of input cross-section points is 32,000. The number of groups that can be calculated
is 200. The number of energy weight pairs for the weighting spectrum is limited to 1300. Any of
these limits can be changed by modifying DIMENSION statements.
7. TYPICAL RUNNING TIME
The sample problem, a 3-group comparison of ENDF/B-IV and -V U-235 data, took only 11.81
seconds of computer time on the IBM 370/3033.
8. COMPUTER HARDWARE REQUIREMENTS
On the IBM 370/3033, the sample problem required 236 K in the GO step.
9. COMPUTER SOFTWARE REQUIREMENTS
A Fortran IV compiler is required.
a. Included in documentation:
A. Alapour, "Informal Notes" (May 1979).
b. Background information:
O. Ozer, "RESEND: A Program to Preprocess ENDF/B, Materials with Resonance Files into a Pointwise Form," BNL-17134 (1972).
D. E. Cullen, "Program LINEAR (Version 79-1): Linearize Data in the Evaluated Nuclear Data File/Version B (ENDF/B) Format," Volume 17, Part A, Rev. 2, UCRL-50400 (October 1979).
D. E. Cullen, "Program SIGMA1 (Version 79-1): Doppler Broaden Evaluated Cross Sections in the Evaluated Nuclear Data File/Version B (ENDF/B) Format," Volume 17, Part B, Rev. 2, UCRL-50400 (October 1979).
J. H., Marable, J. D. Drischler, and C. R. Weisbin, "SENDIN and SENTINEL: Two Computer
Codes to Assess the Effects of Nuclear Data Changes," ORNL/TM-5946 (July 1977).
11. CONTENTS OF CODE PACKAGE
Included are a brief referenced document containing input instructions and one (1.2MB) DOS
diskette which contains the source program and sample problem input and output.
12. DATE OF ABSTRACT
January 1982; August 1984.
KEYWORDS: ENDF FORMAT; MULTIGROUP CROSS SECTION PROCESSING; SENSITIVITY ANALYSIS